INSTALLATION AND INITIAL CONFIGURATION
Prepare Opera for External Scripts by opening Opera’s configuration editor (opera:config) and in the Persistent Storage section set the value “User JS Storage Quota” to at least ?? KB. (TODO: How much should be recommended here? Comments on the developer’s blog say 50 and 1000.) Press “Save”. Restart Opera, then install the extension in the usual way.
I also select “ignore query string” to enable most websites’ search boxes.
TODO: Finish this section.
Facebook users will want to install Facebook Blocker. It allows you to block Facebook scripts from running while on third-party sites. When you’re on Facebook itself, scripts run fine if they are allowed in External Scripts.
If you uninstall External Scripts later, consider returning User JS Storage Quota to its default value of 0.
ALTERNATIVES TO EXTERNAL SCRIPTS
NotScripts is very popular. External Scripts++ is now under development; it will use widget storage instead of script storage and thus be at least theoretically able to synchronize configuration files between installations using third-party services such as SpiderOak.
These notes were last updated on 12 September 2011 with reference to External Scripts 1.21 on Opera 12.02.